#include <iostream>
#include <unistd.h>
#include <stdlib.h>
#include <sys/signal.h>
#include <sys/types.h>
using namespace std;
void hander(int sig, siginfo_t *info, void *myact) {
    printf("hello\n");
}
int main(int argc, char** argv) {
    struct sigaction act;
    int sig;
    sig=atoi(argv[1]);
    sigemptyset(&act.sa_mask);
    act.sa_flags=SA_SIGINFO;
    act.sa_sigaction=hander;

    if(sigaction(sig,&act,NULL) < 0)
    {
        perror("install sigal error");
        return -1 ;
    }
    int a,b;
    while (cin>>a>>b) {
        cout<<a+b<<endl;
    }
    return 0;
}
